Raphicerus sharpei

Geographic Range

Sharpe's grysboks, Raphicerus sharpei , are constrained south of the equator in central and southern Tanzania to northeastern South Africa.

• Biogeographic Regions
• ethiopian ethiopian
  • native native

Habitat

Raphicerus sharpei may be found in a variety of habitats but most often in rocky, hilly country. These animals seem to avoid large areas of grass standing greater than 50 cm tall, and appear to require some shrub thickets and areas with undercover, as are often found in secondary growth forest. Sharpe's grysboks have been documented in areas with little ground cover, though this is abnormal relative to most recorded observations of habitat use.

• Habitat Regions
• temperate temperate
• terrestrial terrestrial

• Terrestrial Biomes
• savanna or grassland savanna or grassland
• chaparral chaparral
• forest forest

Physical Description

Sharpe's grysboks are small, with a mass of 7 to 16 kg, a height of 45 to 55 cm, a head to body length of 65 to 75 cm, a tail length of 4 to 8cm, and a horn length (males only) of about 5 cm. The largest horn length on record is over twice the normal length, at 10.48 cm. Females of this species are slightly larger than the males, but information on individual ranges was not available.

Body color is a rufous to reddish brown broken with speckles of white giving the animal a grizzled appearance. The sides of the face, forehead, upperparts of the muzzle, and outer parts of the limbs are a yellowish-brown color. The belly, underside of the neck, and inside of the legs and ears are a buffy-white. A whitish ring around the eyes extends as a line down the sides of the muzzle to the rhinarium.

Raphicerus sharpei is easily distinguished from other members of the genus. Raphicerus sharpei lacks false hooves as does Raphicerus campestris (steenbok) whereas Raphicerus melanotis (grysbok) has false hooves. The normal tooth formula for Sharpe's grysboks is 0/3 0/1 3/3 3/3. Child and Riney (1964) found only 1 case of abnormal dentition in 121 examined specimens (0.83%) that were from a small area of Southern Rhodesia. The abnormality was found in a female that had upper canines.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

• Sexual Dimorphism
• female larger
• ornamentation ornamentation

Reproduction

Information pertaining to the mating system of the Sharpe's grysboks was not available. However, other members of the genus may be polygynous or pairs may defend territories together. It is likely that these animals are similar to congeners.

Raphicerus sharpei can breed throughout the year. Most records show a peak in breeding between November and December. This proposed peak coincides with the start of the spring rains in southern Africa where this species is found. After a gestation of approximately 180 days (ranging from 168 to 210 days) one to two young will be produced. Weaning of the young will occur at 3 months of age and sexual maturity will be reached for both sexes after 6 to 19 months.

• Key Reproductive Features
• iteroparous iteroparous
• year-round breeding year-round breeding
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• fertilization fertilization
• viviparous viviparous

Little information is available on the parental care of this species. As in other mammals, the female provides the bulk of the parental care. Female Sharpe's grysboks will begin weaning young when offspring reach about 3 months of age. At 6 to 19 months of age, offspring will have reached sexual maturity and are already independent. The role of the father in parental care has not been recorded.

• Parental Investment
• no parental involvement
• altricial altricial
• pre-fertilization
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female
  • protecting
    • female
• pre-independence
  • protecting
    • female

Lifespan/Longevity

Information pertaining to the lifespan/longevity of the Sharpe's grysbok was not available.

Behavior

Sharpe's grysboks are secretive animals, usually spending most of the day lying in thick cover. Their activity is generally nocturnal and solitary. But, although mostly solitary, adult pairs or a female with offspring may be seen throughout the year.

Sharpe's grysboks are territorial, usually defending territories alone, although pairs may defend a single territory together. The male territorial fighting is said to be less ritualistic than in most antelopes, simply involving a straight, forward stride into battle, a lowering to the knees and stabbing or meeting of the short horns.

When frightened by a predator, R. sharpei rarely runs, instead lying flat with an outstretched head and neck in thick undercover until a predator may be nearly on top of them. In the chance that R. sharpei may have to run, such fleeing takes place with a deliberate crouch. An animal stays low to the ground. These grysboks are known to use old burrows, especially those of aardvarks, when in search of protection from predators.

Due to the secretive nature of this species, habit studies are difficult and therefore, relatively little information is known.

• Key Behaviors
• terricolous
• nocturnal nocturnal
• motile motile
• sedentary sedentary
• solitary solitary
• territorial territorial

Home Range

Information pertaining to the home range of R. sharpei was not available.

Communication and Perception

Raphicerus sharpei possesses preputial, eye and facial glands that are used in scent-based communication. In addition, these animals use tactile communication in fighting and mating, as well as between mothers and their offspring. Some visual communication may occur, with regard to body posturing, especially during aggressive encounters.

• Communication Channels
• visual visual
• tactile tactile
• chemical chemical

• Other Communication Modes
• scent marks scent marks

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

All members of the genus Raphicerus are browsers and grazers. A study conducted in southeastern Zimbabwe by Wilson examined the stomachs of 91 R. sharpei specimens and found that it is predominantly a browser, with browse accounting for 70% of the stomach contents. Sharpe's grysboks will feed on some fruit as well as roots and tubers they unearths with their hooves. They apparently do not require access to free water but, if available, will drink it.

• Primary Diet
• herbivore herbivore
  • folivore folivore

• Plant Foods
• leaves
• roots and tubers
• wood, bark, or stems
• fruit

Predation

Sharpe's grysboks usually use thick vegetation and dense undercover to hide from predators. They will use old burrows, especially of aardvarks, as means of evading from predators.

Ecosystem Roles

Little information about the ecosystem roles served by the Sharpe's grysboks has been documented. Given its status as a prey species to numerous predators, it is assumed that its role as a food source for carnivorous predators is important. It is likely to affect vegetative growth through its browsing behavior.

Economic Importance for Humans: Positive

Sharpe's grysboks are of positive economic value to humans as they are hunted for meat, hide and sport in many areas throughout the species' range.

• Positive Impacts
• food food
• body parts are source of valuable material

Economic Importance for Humans: Negative

It has been reported that this species may cause damage to crops.

• Negative Impacts
• crop pest

Conservation Status

Nowak (1991) reported that this species may be threatened by human sprawl in East Africa and has become rare in some parts of their range. The IUCN Red List classifies this species as a lower risk, conservation dependent species (LR/cd). The major threats identified by the IUCN are habitat loss due to the spread of the human population and ongoing harvesting by hunters. Given the large national parks in southern Africa and the populations of Sharpe's grysboks found within these parks, there is little concern of serious decline of this species if continued conservation of National Park land persists.

Other Comments

Historically, Ansell split this R. sharpei into two subspecies. In the northern parts of the range it was classified as R. s. sharpei and in the southern parts of the range was classified as R. s. colonicus . The geographic borders of these subspecies and their validity are still in question. Most literature does not refer to subspecies.

It has been suggested by Kingdon that R. sharpei may be more closely related to the dwarf antelopes of the genus Neotragus than to other species of the genus Raphicerus .

Additional Links

Encyclopedia of Life

Contributors

Nancy Shefferly (editor), Animal Diversity Web.

Scott Hocking (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor, instructor), University of Wisconsin-Stevens Point.

References

Child, G., T. Riney. 1964. Abnormal dentition in the Common duiker (*Sylvicapra grimmia*), Impala (*Aepyceros melampus*) and Sharp's grysbuck (*Raphicerus sharpei*). Occasional Papers of the National museum of Southern Rhodesia , 27B: 1-4.

Nowak, R. 1991. Walker's Mammals of the World- Vol II, 5th ed. . Baltimore, MD, USA: John Hopkins University Press.

Smithers, R. 1983. The Mammals of the Sothern African Subregion . Pretoria, South Africa: University of Pretororia.

Spinage, C. 1986. The Natural History of Antelopes . New York, NY, USA: Facts On File Publications.

African Safari Consultants. 2001. "South Africa Safari" (On-line). Accessed December 02, 2002 at http://www.safariconsultants.com .

IUCN. 2002. "The IUCN Red List of Threatened Species" (On-line ). Accessed 12/02/02 at http://www.redlist.org/search/details.php?species=19307 .